Engine piston



G. DRAKE 1,819,702

ENGINE PISTON Filed April 8, 1930 2 Sheets-Sheet 2 INVENTOR GeorgeBra/(e I BY A1 ATTORNEY 93 of the piston; and

Patented Aug; 18, 1931 c PATENT, "OFFICE" GEORGE DRAKE, F LINDEN, NEWJERSEY ENGINE ris'ron Application filed April 8,

This invention relates to pistons for en gines, such as internalcombustion-motors and similar motors working under pressure,

the object of the invention being to produce a novel form of piston inthe operation of which piston rings may be dispensed with.

It is also an object of the invention to provide a piston for engines bywhich the friction between the piston and the inner wall 1 of the enginepiston is reduced to a minimum, in which also the possibilities forpiston slap and for the scoring of the cylinder walls are divided.

'It is a further object of the invention to provide a piston which willincrease the contact between the cylinder wall and the piston so as tobring about a high compression and expansion without any losses whatever and without any distortion of the cross section of the piston. V

1 With these and, otherobj ects in view which will be hereinafterapparent, the invention consists in the combination and arrangement ofvarious parts as described belowand i1.-

' lust-rated in the accompanying drawings in which 7 Figure 1 is a frontelevation of one for of my new piston; t V Figure 2 is a side elevationof the same;

Figure 3 is a vertical sectional view on line 3-3 of Figure 5;

Figure 4 is avertical sectional view on line 4-4 of Figure 5. r

Figure 5 is a top view of the pistonillus- 3'5 trated in Figures 1-4,with the deta'chably arranged head thereon;

Figure 6 is a top view of the samepiston with the head removedtherefrom;

- Figure 7 is a perspective view of the head F gure 8 is a verticalsectional view, similar to Figure 4, of a piston having the wallarranged in a different way, but being'otherwise unchanged." 9

Like numerals denote like parts in figures.

Referring to the drawings the numeral 10 denotes a pressure receivinghead consisting of a compression ring 11, having a slot 12cut in anysuitable direction. -The upper part all 1930. Serial n 442,425;

of the compression ring 11 is reduced in its 11. An open framework 16,bent-in cylin- I drical fashion and open at its front, is rigidlysecured to, or integrally connected with, the lower rim of thecylindrical part 11 and with the upper rim of a guide ring 17 having thesame diameter as the compression ringll and provided with a split 18arra'nged, as obvious from Figure 1, substantially perpendicularlybelowthe split 12.

It will be noticed fromFigure 2 that th diameter of the cylinder formedby the open fra meworklti is slightlysmaller than that ofthe compressionand guide'rings" 11 and 17 respectively, and that therefore, if inserted tightly into the cylinder '(not shown) of an explosive engine,the parts of the frame-work- 16 will not come into contact with thewalls of aforesaid cylinden i In substantially themiddle of the pistonwrist pin bearings19 andf20- are arranged oppositely to each other andequidistantly from the horizontal axis of the piston, both bearings 19and 20 being integrally connected with the framework 16. c i l FromFigure 1 and particularlyfrom Figure 2 it is apparent that the framework16 is bent intocylindrical shape; there is, how ever, another relationestablished by the parts of this framework 16 insofar as the bearings 19and 20 are concerned,because as seen'from the outside rim of thesebearings 19 and 20, the parts of the framework, extendingsubstantiallyradially from the rims of the bearing to the lower andupper rings 11 and "17, respectively, so as to "form with the outer rimsof these journals a truncated cone and thus with aminimum' of materialevenly support the respective parts, to which they are joined. I v

Figure 7 illustrates a dome-shaped annular plate 21 having a-curved,dome-shaped upper surface 22 and a prismatic body'23, having aconcentric,,arc-shaped peripheral extension 24, which projects beyondtheouter rim of the cylindrical body 11. An elastic double bent flatspring is secured at one end to the plate 21, at its under side in themiddle of the same, while the free end depends and in its normalposition presses against the inside wall of the framework 16, the pointof contact being opposite to the split 12. v

From Figure 3 it is obvious that the domeshaped plate 21 rests safelyupon the shoulder 13 all around the inner cylindrical "wall of the part11 and even reaches into the groove 15, leaving in its normal position asmall free space all around its edge and between the outer wall of thesaid groove 15' and, in this position the plate 21 is normally held byan arc-shaped spring 29interposed, in part in the groove 15, betweensaid plate 21 and the peripheral extension 1 1, the spring 25 reachingalmost all around the plate 21 terminating shortly onboth sides of theprism 23 projecting from the plate 21.

Furthermore the bearings 19 and 20 are rigidly connected with the maincolumn 26 of the framework 16, by two horizontally disposed, arc-shapedribs 27 and 28, respectively.

Figure 8illustrates a piston which in every .respect is the same as theone illustrated in Figures 1-7. Its diflerence from the other piston isbest described by saying that the piston described above is cut int-woparts by a horizontal section through its middle, that the lower sectionis turned. around 180 and then joinedagain to the upperhalf. Thisreversion of the lower half of the piston brings in the new form thusobtained thereby the split 18, of the lower cylindrical part 17,diagonally opposite to the split 18. 1

Furthermore, instead of having only one main column 26, asseen inFigures 1, 2, 3 and 4:, we have now two main columns 26 and 26 slightlylonger than one half of column 26, on the right and left side,respectively of the new piston illustrated by Figure 8.

It is self-evident, that this new piston is open on the side where thesplits 12 and 18 are located, i. e. at the upper left side below split12 and above column 26, and at the right side above split 18 below themain colu1nn'26 Columns 26 and 26 are connected, with the apertures,serving as journalsfor the wristpins, by the ribs 31 and 32.

The prismatic body 23 couldof course not cover and could not protrudebeyond the outer rim of the cylindrical part 11; unless on both sides ofthe split a recess was provided in the rim of the compression ring 11.It is of course necessary that the depth of this recess is not deeperthan the thickness ofthe prismatic body 23, which substantially is thatof the greatest thickness of the plate 21, that is at its center. I

Furthermore this recess 30 must not be wider than necessary to let theprismatic body 23 pass freely in the same and its position must be suchthat said prismatic body 23 covers the split 12.

In regard to the service and the operation of the piston I wish to saythe following:

It is apparent from the sections of the compression ring 11, Figures 3and 4, that the plate 21 rests fully all around upon the shoulder 13 andcovers the split 12 so that the piston is fully covered at its upperpart and assuming that, thermal expansion taken into consideration, itis in proper contact with the inside wall of the cylinder, propercompression of the gas mixture and expansion of the same after explosionis fully guaranteed. To insert the piston, as described above, into thecylinder of an engine, one has first, to push the prismatic body 23 sofar inwardly that itvwill not obstruct any more the insertion of thepiston. Thishaving, been accomplished the spring 25 constantly pushesthe body 23 against the cylinder wall and thus guarantees that theopening of the split 12 is always fully covered so as to prevent thecompressed or expanding gases from escaping without having given offrtheenergy expected from them. Moreover, the arc-shaped spring 29continuously =keeps down the plate 21 upon the shoulder 13 and itsinwardly" disposed terminals,

pressing upon the plate 21, to assist the action of the spring 25pressing the plate 21 towards the wall of the cylinder of the engine.

What I claim is:

1. In a piston of theclass described, the combination'comprising apressure receiving head consisting of a split compression 'ring, and ahorizontal plate slidably arranged in air-tight engagement with the saidsplit compression ring.

2. In a piston of the class described, the combination of a pressurereceiving head consisting of a split compression ring having in itsupper inside wall an annular groove, a recess cut in the wall of saidring at the split and extending on both sides of the split and to thebase of said annular groove, and

a'horizontal plate slidably arranged within and a horizontal plateslidably arranged Within the said annular roove and in airtlghtengagement w th t e said split compression ring, said plate having anarcshaped peripheral extension protruding through said recess to theouter wall of said compression ring to seal the split in saidcompression ring.

4;. In a piston of the class described, the combination comprising apressure receiving head consisting of a split compression ring having anannular groove in its upper inner wall, a recess cut in the wall of saidcompression ring at the split and extending on both sides of the splitand to the base of said annular groove, a dome-shaped plate, having anarc-shaped peripheral extension protruding through said recess, slidablyarranged in said annular groove, the said extension ex tending to theouter wall of said compression ring, and an arcuate elastic ringsuperimposed upon the said plate in the said annular groove adapted tomaintain the said plate in air-tight engagement with the said splitcompression ring.

5. In a piston of the class described, the combination of a pressurereceiving head consisting of a split compression ring having an annulargroove cut in its upper inner wall, a recess cut in the wall of saidring at the split, a dome-shaped plate slidably arranged in said annulargroove having an arc-shaped peripheral extension protruding through thesald recess to the outer periphery of said split compression rlng, anarcuate elastic ring superimposed upon said platein the said annulargroove adapted to maintain the said plate in air-tight engagement withthe said split compression ring, and a double bent flat spring securedat one end to the lower side of saiddome-shaped plate and having itsother end'in engagement with a part of the piston to urge the saidarc-shaped extension into sealing engagement with a cylinder wall.

6. In a piston of the class described, thecombination comprising apressure receiving head consisting of a split compression ring, havingan annular wall portion, and a substantially annular horizontal plateslidably arranged within and near the upper rim of the said annular wallportion, means for re taining said annular plate in air-tight engagementwith said wall portion, an open framework integrally formed with thewall portion of said split compression ring at its upper end and havinga split guide ring integrally formed at its lower end, said openframework being of less diameter than said compression or guide rings,and coaxially arranged wrist pin bearings formed in the said openframework and connected by integral struts to both the said splitcompression ring and the said split guide ring.

7. In a piston of the class described, the combination comprising apressure receiving head consisting of a split compression ring the splitand extending to the base of the said annular groove, a dome-shapedplate slidably arranged in the said annular groove having an arc-shapedperipheral extension protruding through the said recess to the outerperiphery of said split compression ring, an arcuate elastic ringsuperimposed upon the said dome-shaped plate in the said annular grooveadapted to maintain the said plate in air-tight engagement with the saidsplit compression ring, a double bent flat spring secured at one end tothe lower side of said dome-shaped plate and having its free end inengagement with a part of the piston opposite the split to urge the saidarcshaped extension into sealing engagement with a cylinder wall, anopen framework comprising the body of the piston integrally formedwiththe said split compression ring and having a split guide ring at itslower extremity, and co-axially arranged wrist pin bearings formed insaid open framework and connected by integral struts to both the saidsplit compression and split guide rings.

8. In a piston of the class described, the combination comprising apressure receiving head consisting of a'split compression ring having anannular groove formed in its upper inner wall, a recess cut in the wallof said split compression ring, at the split, and extending tothe baseof said groove, a dome shaped plate slidably arranged in said annulargroove having an arc-shaped peripheral extension protruding through saidrecess to the outer periphery of said wall, an arcuate elastic ringsuperimposed upon the" said dome-shaped plate in the said annular grooveadapted to maintain the said plate in airtight engagement with the saidsplit compression ring, a double bent fiat spring se-.

ings at its outer edges in cone-shaped fashion with the rim of both thesaid compression and guide rings with the splits in said ringsvertically aligned with respect to each other.

In witness whereof I have hereunto set my hand.

7 GEORGE DRAKE.

having an annular groove formed in its upper inner wall and a recess cutin the wall at

